Lighting device and vehicle lamp comprising same

ABSTRACT

An embodiment of the present invention relates to a lighting device comprising: a light source unit comprising a plurality of light emitting elements; a conversion unit for converting light emitted from the light source unit; a reflection unit for reflecting light which has passed through the conversion unit; and a half mirror member, which is disposed on the top of the reflection unit, for transmitting a portion of incident light and reflecting a portion of the incident light. The conversion unit includes an optical pattern for selectively transmitting light emitted from the light source unit, the light source unit is disposed on a periphery portion of the reflection unit, and the height of the center portion of the reflection unit is greater than the height of the periphery portion thereof.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/540,572, filed Aug. 14, 2019; which is a continuation of U.S.application Ser. No. 15/780,186, filed May 30, 2018, now U.S. Pat. No.10,422,505, issued Sep. 24, 2019; which is the U.S. national stageapplication of International Patent Application No. PCT/KR2016/014143,filed Dec. 2, 2016, which claims priority to Korean Application No.10-2015-0170372, filed Dec. 2, 2015, the disclosures of each of whichare incorporated herein by reference in their entirety.

TECHNICAL FIELD

The present invention relates to a technology for implementing a threedimensional optical image.

BACKGROUND ART

Light emitting elements including light emitting diodes (LEDs) are beingapplied to various kinds of lighting.

The lighting is being generally applied in a variety of ways, such as toincrease illumination in a limited area, have a uniform luminousefficiency, or adjust the brightness of vehicle lighting needed for apredetermined lighting regulation.

There is an increasing need for utilization of a light emitting elementwhich may be formed to have various shapes or three dimensional effectsin consideration of a design aspect rather than a need for utilizationof a light emitting element as a two dimensional flat light element inapplications of general-purpose lighting.

DISCLOSURE Technical Problem

The present invention is directed to providing a lighting device capableof implementing various optical images by operation of a half mirrormember and operation of a reflective member configured to reflect lightemitted by a light source, and the number of light sources is decreased.

Technical Solution

One aspect of the present invention provides a composite lighting deviceincluding a light source having a plurality of light emitting elements,a first three dimensional light forming part having a reflection unitconfigured to reflect and guide light emitted by the light source, and asecond three dimensional light forming part, which has a half mirrormember configured to transmit or reflect a portion of light reflected bythe reflection unit and a three dimensional structure in which a heightof a central portion of the reflection unit is higher than that of anedge of the reflection unit, disposed above the reflection unit.

ADVANTAGEOUS EFFECTS

According to the embodiment of the present invention, there are effectsthat a lighting device can generate an optical image having variousthree dimensional shapes using a half mirror member and a reflectionunit which reflects light to change a path thereof, and variousfunctions of a two dimensional light source can also be performed evenwhen the number of light sources is significantly decreased.

DESCRIPTION OF DRAWINGS

FIG. 1 is a conceptual exploded perspective view illustrating a lightingdevice according to an embodiment of the present invention.

FIG. 2 is a conceptual view illustrating a coupling cross section ofFIG. 1.

FIGS. 3A-3C are views illustrating various shapes of a reflection unitaccording to an embodiment of the present invention.

FIG. 4A is an image showing a shape of an optical pattern member.

FIG. 4B is an image showing a front view of the lighting device in whichan image is generated.

FIG. 4C is an image showing a side view of the lighting device in whichthe image is generated.

FIG. 5A is an image showing a shape of the optical pattern member.

FIG. 5B is an image showing the lighting device, in which the image isgenerated, seen from a first angle.

FIG. 5C is an image showing the lighting device, in which the image isgenerated, seen from a second angle.

FIG. 5D is an image showing the lighting device, in which the image isgenerated, seen from the first angle.

FIGS. 6 and 7 are images showing examples in which the lighting deviceis formed according to the embodiment of the present invention.

MODES OF THE INVENTION

A configuration and operations of the present invention will bedescribed below in further detail with reference to exemplaryembodiments of the present invention. When the present invention isdescribed with reference to the accompanying drawings, components thatare the same regardless of reference numerals will be referred to by thesame reference numerals, and redundant descriptions thereof will beomitted. While terms “first,” “second,” etc. may be used to describevarious components, such components may not be limited to the aboveterms. The above terms are used only to distinguish one component fromanother component.

FIG. 1 is a conceptual exploded perspective view illustrating a lightingdevice according to an embodiment of the present invention, and FIG. 2is a conceptual view illustrating a coupling cross section of FIG. 1.

Referring to FIGS. 1 and 2, the lighting device according to theembodiment of the present invention includes light sources 100A and 100Bhaving a plurality of light emitting elements 110, a first threedimensional light forming part having a reflection unit 130 configuredto reflect and guide light emitted from the light sources 100A and 100B,and a second three dimensional light forming part disposed above thereflection unit 130 and having a half mirror member 140 configured totransmit and reflect a portion of light reflected by the reflectionunit.

The first three dimensional light forming part may include a frame ofthe reflection unit 130 and may further include conversion units 150disposed at both sides or one side of the reflection unit 130.Particularly, in this case, the reflection unit 130 according to theembodiment of the present invention may have a three dimensionalstructure in which a height h1 of a central portion is higher thanheights h2 and h3 of edge portions.

In the lighting device according to the embodiment of the presentinvention having the above-described structure, light passing throughthe conversion unit 150 is guided upward by being reflected by a surfaceof the reflection unit 130, and then various optical images may begenerated by the half mirror member 140 configured to transmit a portionof light and reflect the remaining light.

The light sources 100A and 100B may be disposed in a longitudinaldirection of the reflective member 140, the light emitting elements 110may be mounted on printed circuit boards 120, and the plurality of lightemitting elements may be disposed to be spaced apart from each other inone direction.

In the embodiment, the light emitting elements 110 may be disposed on ahousing C to emit light toward an inclined surface of the reflectivemember 140 as illustrated in the drawings. The light emitting element110 may include any one selected from among a light emitting diode(LED), an organic LED (OLED), a laser diode (LD), a laser, and avertical-cavity surface-emitting laser (VCSEL). In the embodiment of thepresent invention, the light emitting element is exemplarily illustratedas an LED.

As illustrated in FIGS. 1 and 2, a first light source 100A and a secondlight source 100B may be disposed adjacent to both edges of thereflection unit 130 with respect to the central portion of thereflection unit 130.

The conversion units 150 may be interposed between the reflection unit130 and the first light source 100A, and between the reflection unit 130and the second light source 100B. In this case, light al emitted by thelight sources 100A and 100B may reach the reflection unit 130 via thediffused light conversion units 150.

In the embodiment, the light sources are exemplarily illustrated to bedisposed at both sides of the reflection unit 130, but are not limitedthereto, and the light source may be disposed at only one side of thereflection unit.

Hereinafter, a configuration and a function of the present inventionwill be described on the basis of the first light source 100A disposedat one side thereof because the light sources 100A and 100B have thesame configuration and perform the same function.

In a case in which the first light source 100A emits light, the lightmay pass through the conversion unit 150. As illustrated, the lightsource 100A is spaced apart from the conversion unit 150, and an airlayer is formed between the both components, but in another embodiment,a gap between the both components may be filled with a resin layer.

The conversion unit 150 may include a diffusion member 151 configured todiffuse light emitted by the light emitting element 110 and an opticalpattern member 152 disposed on one surface of the diffusion member 151.

The diffusion member 151 performs a function of diffusing light, and anysheet or member having a known diffusion function may be used as thediffusion member 151. As an example, a synthetic resin having high lighttransmittance may be applied as the diffusion member 151, andpolyethyleneterephthalate, polyethylene naphthalate, acrylic resin,colicarbonate, polystyrene, polyolefin, cellulose acetate,weather-resistant vinyl chloride, or the like may be applied as thediffusion member 151, but the diffusion member 151 is not limitedthereto. In addition, a material capable of having a diffusion functionsuch as acrylic, polymethyl methacrylate (PMMA), cyclic olefin copoly(COC), polyethylene terephthalate (PET), and high permeability plasticssuch as a resin may be applied as the diffusion member 151.

The optical pattern member 152 images a shape of light emitted by thelight emitting element 110, and an optical pattern for imaging variousshapes of light may be formed on the optical pattern member 152. As anexample, the optical pattern member 152 may generate various shapes oflight by forming fine slit patterns in a sheet having a reflectiveproperty to transmit a portion of the light through the slit patterns,or by using a translucent material having a shape of an optical patternto transmit a portion of the light through the translucent material.

The reflection unit 130 may have a structure in which a thicknessdecreases from the central portion of the reflection unit (the height h1which is an upper reference point) toward the edges (the heights h2 andh3). Particularly, the reflection unit 130 may have a three dimensionalstructure including a first side surface 131 configured to reflect lightemitted by the first light source 100A, and a second side surface 132configured to reflect light emitted by the second light source 100B.

Accordingly, as illustrated in FIGS. 3A-3C, the reflection unit 130according to the embodiment of the present invention may be implementedto have a three dimensional structure having a width and a length,wherein the first side surface is in contact with the second sidesurface at the central portion of the reflection unit, and each of thefirst side surface and the second side surface may have a structure of aflat or curved surface. In addition, the reflection unit may beimplemented to have a structure allowed to be filled with a material ora hollow structure as illustrated in FIG. 3C.

In addition, the reflection unit 130 may be formed of a reflectivematerial having a reflective property or may also be formed of aseparate material with a reflective material applied on a surface of thereflection unit 130. A metal layer such as Ag having a high reflectiveproperty may be used as the reflective material, or a surface of a metalor synthetic resin material may be coated with a reflective materiallayer formed of TiO₂, CaCo₃, BaSo₄, Al₂O₃, silicon, polystyrene (PS), orthe like to form the reflective material. In addition, a surface of ametal or synthetic resin material may be coated with titanium oxide,aluminum oxide, zinc oxide, lead carbonate, barium sulfate, or calciumcarbonate to form the reflective material, or a synthetic resin layerincluding the above-describe material may be formed as the reflectivematerial. In addition, any one among aluminum (Al), polycarbonate (PC),polypropylene (PP), acrylonitrile butadiene styrene (ABS), andpolybutylene terephthalate (PBT) having a reflective property may alsobe used to form the reflective material.

In addition, as another example of the reflective material, thereflective material may be formed as a film type, and may be formed byincluding a synthetic resin containing a dispersed white pigment toimplement improvement of a light reflective property and a lightdispersion property. For example, titanium oxide, aluminum oxide, zincoxide, lead carbonate, barium sulfate, calcium carbonate, or the likemay be used as the white pigment, and polyethyleneterephthalate,polyethylene naphthalate, acrylic resin, colicarbonate, polystyrene,polyolefin, cellulose acetate, weather-resistant vinyl chloride, or thelike may be used as the synthetic resin, but the white pigment and thesynthetic resin are not limited thereto.

An operating principle of the lighting device according to theembodiment of the present invention will be described with reference toFIG. 2.

Referring to FIG. 2, the conversion unit 150 may be disposed adjacent toan outer side of the reflection unit 130. In this case, a concept of“being disposed adjacent to” includes a concept in which the reflectionunit 130 and the conversion unit 150 are pressed against each other orare disposed to be spaced by a predetermined distance. However, in thecase of the lighting device, the lighting device may further include theexternal housing C accommodating the light sources 100A and 100B, thereflection unit 130, and the conversion unit 150 therein.

For example, light al emitted by the first light source 100A may passthrough the conversion unit 150 and diffuse to be shaped into an imagepatterned by the optical pattern member 152. Then, the light shaped intothe image may be reflected by the first side surface 131 of thereflection unit 130.

A portion a3 of the light penetrates the half mirror member 140 disposedat an upper portion of the housing C, and the remaining portion a4 ofthe light may return to the reflection unit 130. Then, the light may becontinuously reflected while a portion of the light penetrates the halfmirror member 140 and the remaining portion of the light is reflected bythe half mirror member 140 (a5 to a7) to generate a plurality of opticalimages (see FIG. 4A to FIG. 4C).

In the embodiment of the present invention, the reflection unit 130 mayrealize such a repeated reflection process to maximize light useefficiency, and the reflection unit 130 and the half mirror member mayalso generate a plurality of optical images.

The half mirror member 140 may include a member formed of a materialwhich transmits a portion of light and reflects the remaining portion ofthe light. As an example, the half mirror member may include a filmmember having a structure in which a metal layer is deposited on a basematerial. The base material may be one of various synthetic resin films,and the metal layer may be formed by depositing or applying adepositable metal material, such as Ni, Cr, Al, or Ti, on a filmmaterial. The half mirror member is a general member which transmits aportion of light and reflects the remaining portion of the light.

In addition, in order to increase optical reflection efficiency, anuppermost portion of the central portion of the reflection unit 130 maybe disposed to be spaced apart from a lower surface of the half mirrormember 140. In addition, in order to increase light use efficiency andsupport the half mirror member 140, a structure having an upper portionof the conversion unit 150 in contact with the half mirror member 140may be realized.

Furthermore, in a structure shown in FIG. 2, in consideration of a firstregion d1 corresponding to a width of the reflection unit 130 and asecond region d2 corresponding to a space between the conversion unitand the lighting unit, the half mirror member 140 may be disposed tocover upper surfaces of the first region d1 and the second region d2.

In this case, various optical images may be generated as threedimensional images in the first region d1 as described above, andsurface lighting may be performed in the second region d2, and thuscomposite lighting may also be realized. In the embodiment of thepresent invention, the term “three dimensional light” is defined as thatan image of light emitted by a light emitting surface of the lightingdevice is generated to have a predetermined feeling of depth or volume.

In addition, in a case in which the half mirror member is disposed onthe upper surface of the first region d1 and a second diffusion memberis additionally disposed on the second region d2, surface lightingefficiency in the second region may be further increased. In such anarrangement structure, there is an advantage in that light useefficiency may be maximized because lighting is performed by even theupper portion of the second region when one light source is used.

In the embodiment, a plurality of light components emitted by aplurality of light sources may be converted into a predetermined imageby the diffusion member 151 and the optical pattern member 152. Forexample, when the optical pattern is a plurality of holes each having atriangular shape, light which passes through the optical pattern member152 may be converted into an image in which a plurality of triangularshapes are disposed in a longitudinal direction of the optical pattern.Then, the light converted by the optical pattern member 152 may have afeeling of depth due to the half mirror member 140.

FIGS. 4A to 4C are images showing examples in which the lighting devicehaving the structure of FIG. 2 is formed according to the embodiment.

Referring to FIGS. 4A to 4C and 2, in the example of the optical patternmember 152 of FIG. 4A, the optical pattern 153 is formed to have apenetrating structure or a transparent structure that light maypenetrate, and other portions thereof are formed to have a structureincluding a shielding or reflective material. A shape of the opticalpattern is not limited particularly. For example, the shape of theoptical pattern may be a polygonal shape, such as a triangular shape anda tetragonal shape, or a circular shape.

FIG. 4B is an image of the lighting device when the lighting device isturned on and viewed from an upper front of the half mirror member 140in a case in which the lighting device is formed to have the structureof FIG. 2. A shape of an optical image of which lateral sides areentirely connected and have curvatures in a depth direction may berealized by adjusting the optical pattern members disposed at the leftand right sides, the central portion, and inclination angles and heightsof the edges of the reflection unit.

The light source is disposed at a lower portion of the second region d2,and even in a case in which a minimum number of lighting elements havingLEDs are turned on at a thin printed circuit board, a depth feelingdeeper than a total thickness of the lighting device may be felt, andvarious optical patterns may be realized as illustrated in the drawing.

Even in the case of a side view of the lighting device as illustrated inFIG. 4C, a depth feeling may be felt, and accordingly, even in a case inwhich a minimum number of light sources are used in the lighting deviceaccording to the present embodiment, an optical pattern by which aplurality of three dimensional effects are realized may be provided.

FIGS. 5A to 5D illustrate examples of felt depth feelings in cases inwhich the reflection unit 130 of the present invention having thestructure shown in FIG. 2 has a structure in which a height of thecentral portion is almost similar to that of the edges so that thereflection unit 130 is substantially flat, that is, an inclination angleformed by the central portion, the edges, and a lower flat surface ofthe reflection unit ranges from 150° to 180°. In a case in which anangle of the reflection unit is wide, left and right optical imageswhich are not connected and descend in a depth direction may berealized. In addition, even in a case in which the optical patterns areformed to be the same, an image in which light continues in a depthdirection of the lighting device may be realized as the inclinationangle of the reflection unit is decreased. Such a three dimensionalfeeling may be variously felt according to a direction from which thelighting device is seen as illustrated in FIGS. 5B to 5D.

FIG. 6 is an image of the lighting device when a first diffusion member145 is disposed at portions of the second regions d2 and d3 instead ofthe half mirror member 140 of FIG. 2 or a diffusion member is stacked onan upper surface of the half mirror member. As illustrated in thedrawing, a three dimensional optical image may be realized in the firstregion d1, surface lighting may be performed from the second region, andthus various lighting effects may be obtained.

In addition, a second optical member for implementing three dimensionallight may also be disposed at the second regions d2 and d3. The secondoptical member may be a light transmission sheet member having anembossed pattern on a surface of a material and may generate a threedimensional optical image of a portion of light, which is directlytransmitted upward and not transmitted toward the conversion unit 150,emitted by the light source.

In addition, as illustrated in FIG. 7, an image of light emitted from apoint light source shown in the half mirror member 140 may also begenerated as an image of a plurality of point light sources.

In various embodiments of the present invention, as transmissivity ofthe half mirror member is decreased, the number of generated illusionsof light is increased. This is because an amount of light reflectedtoward an inside of the lighting device by the half mirror member isincreased so that the number of repeated reflections in the lightingdevice is increased. Accordingly, since the half mirror memberconfigured to reflect light guided by the reflection unit is disposed inthe lighting device according to the embodiment of the presentinvention, an image or character having a three dimensional feeling maybe generated, and this may be further enhanced by adjustingtransmissivity of the half mirror member, and such a three dimensionalfeeling may be further variously provided by forming the above-describedshapes or arrangement structures of the reflection unit and the opticalpattern layer.

The lighting device according to the embodiment of the present inventionmay be applied to various lamp apparatuses such as a vehicle lamp, ahousehold lighting device, and an industrial lighting device thatrequire lighting. For example, in a case in which the lighting device isapplied as a vehicle lamp, the lighting device may be applied as aheadlight, a vehicle interior lighting, a door scuff, a backlight, orthe like. In addition, the lighting device according to the embodimentmay also be applied to the field of a back light unit applied to aliquid crystal display apparatus and in addition, may also be applied toa field related to lighting which is developed and commercialized or canbe realized according to technical development in the future.

In the detailed specification of the present invention, specificembodiments have been described above. However, various modificationsmay be made without departing from the scope of the present invention.The technical spirit of the present invention should not be defined bythe described embodiments of the present invention and should be definedby the claims and equivalents thereof.

1. A lighting device comprising: a first light source including aplurality of light emitting elements; a second light source disposedopposite to the first light source and including a plurality of lightemitting elements; a first conversion unit disposed on a path of lightemitted from the first light source; a second conversion unit disposedon a path of light emitted from the second light source; a reflectionunit disposed between the first conversion unit and the secondconversion unit; and a half mirror member spaced apart from thereflection unit, wherein light emitted from the first light source andpassing through the first conversion unit is reflected by the reflectionunit, and wherein a height of a central portion of the reflection unitis greater than a height of both edges of the reflection unit.
 2. Thelighting device of claim 1, wherein the reflection unit comprises afirst side surface disposed between the center portion and one edge ofthe both edges, and a second side surface disposed between the centerportion and the other edge of the both edges, wherein each of the firstside surface and the second side surface has a flat or curved surfacestructure.
 3. The lighting device of claim 2, wherein a vertical crosssection of the reflection unit comprises a semicircular structure. 4.The lighting device of claim 2, wherein a vertical cross section of thereflection unit comprises a triangular structure.
 5. The lighting deviceof claim 2, wherein the reflection unit has a structure in which a spaceis formed on an inner side surface of the reflection unit.
 6. Thelighting device of claim 1, wherein the first conversion unit and thesecond conversion unit comprise a diffusion member and an opticalpattern member, wherein the diffusion member and the optical patternmember are disposed so that light emitted from the first light sourceand the second light source passes through the optical pattern memberafter passing through the diffusion member.
 7. The lighting device ofclaim 6, wherein the both edges of the reflection unit are disposed soas to be in contact with the optical pattern member.
 8. The lightingdevice of claim 7, wherein the optical pattern member is configured toselectively transmit the light emitted by the first light source and thesecond light source.
 9. The lighting device of claim 8, wherein theoptical pattern member comprises a plurality of optical patterns, andwherein shapes of the optical patterns include triangular, tetragonal,or circular shapes.
 10. The lighting device of claim 9, wherein theplurality of the optical patterns is formed in a structure penetratingone region of the optical pattern member.
 11. The lighting device ofclaim 10, wherein a size of each optical pattern of the plurality of theoptical patterns is different.
 12. The lighting device of claim 1,wherein a first portion of the light reflected by the reflection unitpasses through the half mirror member, and a second portion of the lightreflected by the reflection unit is reflected from the half mirrormember to the reflection unit.
 13. The lighting device of claim 6,wherein the both edges of the reflection unit are disposed so as to bein contact with the optical pattern member.
 14. The lighting device ofclaim 1, wherein the central portion of the reflection unit is spacedapart from a lower surface of the half mirror member.
 15. A vehicle lampcomprising the lighting device of claim 1.